The effect of local Sn-doping on the photoluminescence (PL) properties of the Si-rich silica (SRSO) thin film was investigated. In order to dope Sn into the SRSO film, we introduced a Sri interlayer in the film. After annealing at temperatures higher than 1000 degrees C, the PL intensity of the Sn-doped samples was about 2 times higher than that of the undoped ones, while Sn-doped and undoped samples annealed at lower temperatures had almost the same PL intensities. The microstructure and mechanism of the PL improvement of this SiOx/Sn/SiOx system were analyzed by Raman scattering spectroscopy, Auger electron spectroscopy, and X-ray diffraction. (c) 2007 Elsevier B.V. All rights reserved.